The objectives are (A) to study the synthesis of galactosylretinyl phosphate in intestinal mucosa in suspensions of intestinal cells in a crypt-to-villus gradient, by incubating with labeled galactose and retinol (or retinyl) phosphate) free, or bound to retinyl binding protein. Galactosylretinyl phosphate synthesis and transfer of galactose to glycoprotein will be correlated with stages of differentiation. (B) The objective of this portion of the project is to use the monospecific antibody we have prepared against pure alpha 1-macroglobulin of the rat, to explore the way in which vitamin A affects the synthesis of this serum protein in liver: whether by involvement of addition of sugar residues, which sugar residues and in which position; or whether the whole molecule is affected. Is there less alpha 1-macroglobulin made by deficient liver or is an abnormal glycoprotein made with less mannose? We would determine whether mannosylretinyl phosphate is involved in its synthesis and, by making modified alpha 1-macroglobulin acceptors, whether mannosylretinyl phosphate can transfer mannose to alpha 1-macroglobulin. (C) To determine the biochemical parameters of the synthesis of mannosylretinyl phosphate and of the transfer of mannose from it to protein, including the nature of the acceptor in liver microsomes.